The rose diagram shows only the swells directed at Haqal that coincided with light winds or offshore conditions through a typical September. It is based on 1680 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. Green and yellow represent increasing swell sizes and highest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the most common swell direction, shown by the longest spokes, was S, whereas the the dominant wind blows from the SSW. The chart at the bottom shows the same thing but without direction information. For example, swells larger than 1.5 feet (0.5m) coincided with good wind conditions 77% of the time, equivalent to 23 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal September but 18% of the time we expect swell in the range 2-3m (6.5-10ft) 18%, equivalent to (5 days). Taking into account the fraction of these swells that coincided with forecast offshore winds, and given the fact that Haqal is exposed to open water swells, we calculate that clean surf can be found at Haqal about 77% of the time and that surf is spoilt by onshore wind 23% of the time. This is means that we expect 30 days with waves in a typical September, of which 23 days should be surfable.
IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.